APA (7th ed.) Citation

Renn, L., Muir, W., & Muir, E. (1931). ... After war. M. Secker.

Chicago Style (17th ed.) Citation

Renn, Ludwig, Willa Muir, and Edwin Muir. ... After War. London: M. Secker, 1931.

MLA (9th ed.) Citation

Renn, Ludwig, et al. ... After War. M. Secker, 1931.